New 4GB DIMM's in iMAC Aluminum 20"?

I have an iMac 2.0GHz Intel Core 2 Duo (20-inch) MA876LL. I'm big into desktop virtualization (using VMware fusion) so obviously the upgrade to 4GB is key. I have 1GB now mostly because I have been using it as an internet terminal, but it's still real slow.

I would like to upgrade to 4GB- but I noticed they now sell 4GB DIMM's.

Will the BIOS/MB refuse 2x4GB DIMM's for a total of 8GB? Any hacks or upgrades I could do to get 8GB in this machine?

Also is the CPU socketed or soldered into the motherboard (I'm thinking the iMAC's use the same or similar motherboards as their laptops). If I could open this puppy up and drop in a 3GHZ C2Duo that would rock, but totally void warranty however.

Just some questions. If I want a faster 20" maybe the 2.66ghz I might just have to sell the one I have now and buy a refurb or one on ebay....

I have an iMac 2.0GHz Intel Core 2 Duo (20-inch) MA876LL. I'm big into desktop virtualization (using VMware fusion) so obviously the upgrade to 4GB is key. I have 1GB now mostly because I have been using it as an internet terminal, but it's still real slow.

I would like to upgrade to 4GB- but I noticed they now sell 4GB DIMM's.

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It will not see beyond 4GB ram even if it would boot with that memory.

If it does indeed boot then we know the iMac is capable of addressing more ten the 4GB of memory stated in the system specifications.

My only concern with putting in 4GB and 1GB is that memory is supposed to be installed in matched pairs for optimal performance but it would be interesting to see if it works with more than 4GB of memory.

If it does indeed boot then we know the iMac is capable of addressing more ten the 4GB of memory stated in the system specifications.

My only concern with putting in 4GB and 1GB is that memory is supposed to be installed in matched pairs for optimal performance but it would be interesting to see if it works with more than 4GB of memory.

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Not really the Mac Mini will run with two 2GB sticks, but the computer will only be able to access 3GB of it.

Not really the Mac Mini will run with two 2GB sticks, but the computer will only be able to access 3GB of it.

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That's because of the chipset. It can't address more than... wait... I was going somewhere with this... I HAD a side to this... I just can't figure out how to word it properly.

Apple always understates the amount of RAM that you can put in their machines. The iMac DV can address 1GB, but Apple said the max was 512MB. Sometimes the limit they impose is due to the prohibitive cost of RAM at the time. Another example: the original Mac Pro was never touted to be able to use more than 16GB, but it, like the current one, can use 32GB. 4GB FB-DIMMs didn't exist at first, and when they started to come out, they were prohibitively expensive. Try ludicrously.

Apple always understates the amount of RAM that you can put in their machines. The iMac DV can address 1GB, but Apple said the max was 512MB. Sometimes the limit they impose is due to the prohibitive cost of RAM at the time. Another example: the original Mac Pro was never touted to be able to use more than 16GB, but it, like the current one, can use 32GB. 4GB FB-DIMMs didn't exist at first, and when they started to come out, they were prohibitively expensive. Try ludicrously.

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No, Apple does not ALWAYS understate the RAM. It has happened in the past, but is not an indicator that it is Apple's policy to do with all machines.

Apple's technical documents state unambiguously that the maximum readable device (chip) size is 1024 MBits, and the maximum readable number of devices on a module is 16. That means a maximum 2 GB module. Unless Apple is lying, that is the state of it until it can be shown to be wrong.

I'm on a Mac Pro with 8GB of memory and if the iMac could accept more than 4GB, even 5GB, I'd sell my Mac Pro and jump on the iMac in a heart beat. I know the previous iMacs could only support 3GB but if you put in 4GB it saw 3.3GB right?

The only problem that I might have, is that these 4GB sticks are for servers. They use a technology called buffered ECC, to prevent internal memory errors. I am not sure if iMac's- or any mac for that matter, can use bufffered ECC memory- simply because the pin outs are different, I THINK. Since they are meant for servers, and "registered" memory is for "personal computers".

The only problem that I might have, is that these 4GB sticks are for servers. They use a technology called buffered ECC, to prevent internal memory errors. I am not sure if iMac's- or any mac for that matter, can use bufffered ECC memory- simply because the pin outs are different, I THINK. Since they are meant for servers, and "registered" memory is for "personal computers".

Ahh crap. Well I guess that settles that! I should have bothered to read the instructions that came with the iMac on how to install memory, they probably would have showed a picture of the SODIMM I figured since this machine is a "desktop" it would use desktop memory.

So I guess all the iMac is is a Macbook Pro / Powerbook / whatever they're calling them now in a low foot print case with a big ass display?

Lacking any other specification these are the facts as they stand now. If new technology becomes available after the specifications are created that permit larger memory then that will change things, but right now its limited to 4GB.

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